WO2022027530A1

WO2022027530A1 - Blockchain-based high-performance tamper-proof database construction method

Info

Publication number: WO2022027530A1
Application number: PCT/CN2020/107591
Authority: WO
Inventors: 李兴华; 任彦冰; 胡中元; 李小强; 王运帷; 王航
Original assignee: 西安电子科技大学
Priority date: 2020-08-05
Filing date: 2020-08-07
Publication date: 2022-02-10
Also published as: CN112115116A; CN112115116B

Abstract

The present invention pertains to the technical field of blockchains, and discloses a blockchain-based high-performance tamper-proof database construction method. The construction method comprises: a double-layer database system structure based on a distributed peer-to-peer network; low-time complexity data self-checking and inter-node mutual checking methods; and a modular configurable system architecture. The invention solves the single-point-of-failure problem of traditional data systems, establishes an efficient B+ tree-based indexing structure, and eliminates the bottleneck of low query performance under traditional blockchain architectures. The method solves the problem of high-speed verification for big data, realizes data tamperproofing and deletion protection in double-layer database architectures, and meets the demand of enterprises for trusted storage of sensitive data. The invention realizes customizability and scalability of system functions, meets various security requirements of different service scenarios, and reduces the cost of actual deployment processes for the enterprises. The present invention realizes data tamperproofing and deletion protection in double-layer database architectures, and achieves customizability and scalability of system functions.

Description

A construction method of a high-performance anti-tampering database based on blockchain

technical field

The invention belongs to the technical field of blockchain, and in particular relates to a method for constructing a high-performance anti-tampering database based on blockchain.

Background technique

At present: the database system belongs to the basic and supporting software, which is widely used in major national industries such as government affairs and commerce, military defense, aerospace, banking and securities, and medical and health care. It is a key technology that is stuck by foreign countries. Under the trend of informatization and intelligence in today's society, data is the core and foundation of information systems, and data security is a key factor related to national security and social stability. In March 2020, the Standing Committee of the Political Bureau of the Central Committee of the Communist Party of China held a meeting, pointing out that the construction of new infrastructure such as data centers should be accelerated; in April 2020, the Central Committee of the Communist Party of China and the State Council issued the "Opinions on Building a More Perfect Market-based Allocation System and Mechanism for Factors" List data as one of the five core elements. As the foundation and support of data storage, management and processing, the security and efficiency of database system are important for developing new infrastructure construction such as data centers, giving full play to the role of data basic resources and strategic resources, and exploring new technologies with data as the key element. Growth patterns are significant.

Although the database system is of great significance for economic development and new infrastructure construction, it has the following challenges in terms of security: 1) the traditional centralized database faces the risk of single-point failure during data storage, 2) the data stored in the database system It is easy to be illegally tampered with and difficult to detect. Therefore, ensuring the high availability and immutability of data in the database storage system is the key to data security.

In order to solve the above problems, the distributed database based on blockchain came into being. Compared with traditional databases, it has the advantages of decentralization, immutability, openness and transparency. However, the existing blockchain databases still cannot meet the needs of enterprise business systems. The main problems include: 1) Most existing blockchain databases use non-relational storage structures, which are inefficient in data retrieval. Problems; 2) The existing blockchain database does not support customized expansion at the data storage level, and requires enterprises to make a lot of additional adaptations to apply to existing business systems.

Through the above analysis, the existing problems and defects in the prior art are:

(1) Most of the existing blockchain databases use a non-relational storage structure, which has the problem of low efficiency in data retrieval.

(2) The existing blockchain database does not support customized expansion at the data storage level, and requires enterprises to make a lot of additional adaptations to apply to existing business systems.

SUMMARY OF THE INVENTION

Aiming at the problems existing in the prior art, the present invention provides a method for constructing a high-performance tamper-proof database based on blockchain.

The present invention is implemented in this way, a method for constructing a high-performance anti-tampering database based on blockchain, and the method for constructing a high-performance anti-tampering database based on blockchain includes:

Two-layer database system structure based on distributed peer-to-peer network: data is divided into two layers through hierarchical design, the bottom layer is the incremental data change stored in the blockchain data structure, and the chain data structure has a higher tail write Performance, the top layer is the final state set of data obtained by incremental changes in the underlying data, which is stored in a block structure, and uses a B+ tree to build an index;

Data self-inspection and inter-node mutual inspection method with low time complexity: the bottom layer uses the blockchain data structure for storage, through regular self-inspection of the chain structure's legitimacy, and through inter-node communication to correct the tampered data, the top layer is stored The final state of the data, the top-level database performs self-checks before operating on the data;

Modular and configurable system architecture: It provides a pluggable automatic cleaning function, supports a modular consensus mechanism replacement scheme, and supports the required functional expansion at the application layer under the existing blockchain double-layer architecture.

Further, the method for constructing the blockchain-based high-performance anti-tampering database includes:

(1) Double-layer database system structure based on distributed peer-to-peer network;

(2) Data self-checking and inter-node mutual checking methods with low time complexity;

(3) Modular and configurable system architecture.

Further, the described double-layer database system structure based on distributed peer-to-peer network includes the following steps:

Step 1: Divide the data into two layers through hierarchical design;

Step 2, the bottom layer is the incremental data change stored in the blockchain data structure, and the chain data structure has higher tail write performance;

Step 3: The top layer is the final state set of data obtained by incremental changes of the underlying data, which is stored in a block structure and indexed using a B+ tree.

Further, the step 1 divides the data into two layers by hierarchical design and includes the following steps: the bottom layer is the data change increment stored by using the blockchain data structure, and the top layer is the final data state set obtained from the bottom layer data change increment; The bottom layer adopts relational database for structured storage, and the top layer adopts the database type required by the business.

Further, in the second step, the bottom layer is the data change increment stored in the blockchain data structure, and the chain data structure has higher tail write performance, including the following steps:

(1) Accept the user's on-chain request through the API;

(2) The on-chain request is broadcast among nodes in the form of a pending on-chain transaction;

(3) When the consensus block time arrives, the node will package the current transaction to be listed as a block;

(4) Follow the blockchain data structure and store in the underlying blockchain database.

Further, in the step 3, the top layer is the final state set of data obtained by incremental changes of the underlying data, which is stored in a block structure, and uses B+ tree to build indexes at the same time, which has higher query performance, including the following steps:

(1) Whenever a node generates a block, or obtains an updated block from other nodes, the data changes in the new block will be incrementally reproduced in the top-level state database, and the top-level state database will be the latest state;

(2) Use the B+ tree to build an index.

Further, the method for data self-checking and inter-node mutual checking with low time complexity includes the following steps:

(1) The bottom layer adopts the block chain data structure for storage, and the tampered data is corrected through the regular self-check of the chain structure's legitimacy through communication between nodes;

(2) The top-level database performs self-inspection before operating the data.

Further, in the first step, the bottom layer adopts the blockchain data structure for storage, and the tampered data is corrected through the regular self-check of the chain structure's legitimacy, and the tampered data is corrected through the communication between nodes, so as to ensure that the data on the chain cannot be tampered with; Include the following steps:

(1) First, the node performs a self-check to check whether the hash before and after its own blockchain is correct; if it is not performed correctly (2); the node performs a self-check before operating the data in the top-level database; including the following steps:

The node calculates the hash value of the current latest state of the top-level database, broadcasts the hash value to the entire network, and then uses the modular consensus protocol to confirm that the state of its top-level database is currently consistent across the entire network;

If the node learns that the current hash value of its top-level database is different from that of more than 1/2 of the nodes in the entire network through the consensus process, the node will call the self-check and mutual-check process of the underlying blockchain to check the latest status of the bottom and top-level databases. Synchronize;

If the node confirms that the current hash value of its top-level database is consistent with more than 1/2 of the nodes in the entire network through the consensus process, it will continue to add, delete, and modify the database, and send the SQL statement of the top-level database operation to the underlying blockchain. Database network to achieve;

(2) Broadcast the request message to the blockchain nodes with physical connections around it; including the following steps:

1) Request message: Node X first broadcasts the message Request={Cert_X, t, Nonce, Sign(Sk _x , H(Cert_X||t||Nonce))}; Among them, Cert_X represents the public key certificate of node X, t is the maximum block number of the current local blockchain, and Nonce is the selected random number;

2) Response message: After the neighbor node receives the Request, it first verifies its signature information to ensure the authenticity of the source of the request message and the integrity of the content, and then sends a response message Response containing the missing blockchain to the requesting node X ; Take one of the neighbor nodes K as an example, Response_K={Cert_K, Block_lost, Nonce+1, Sign(Sk _x , H(Cert_K||Block_lost||Nonce+1))}; wherein, Cert_K represents the response of the neighbor node K Public key certificate, Block_lost indicates the discarded block set Block_lost={Block _t+1 ,..., Block _n } (assuming that the latest block of the entire network is Block _n ), node X will receive responses from multiple neighbor nodes , and recover all lost block data by selecting the response message that contains the most lost block sets and is valid for verification. The verification here includes the verification of the chain relationship in the block and the verification of the signed message.

Further, the modular and configurable system architecture includes the following steps:

(1) For the underlying blockchain database, a modular consensus mechanism replacement scheme is supported, and a Raft-based consensus protocol with both security and consensus efficiency is built in. Users can also switch to the PBFT consensus protocol with higher security, or Manually specify the block time;

(2) The top-level database supports data access through various interfaces, compatible with various common database accesses, including relational databases postgres, mysql, supports users to choose according to business needs, and supports queryers to submit query requests using standard SQL statements, including Filter, cluster, join, sort complex operations;

(3) Provides a pluggable automatic cleaning function, which can be freely configured to store transaction data in recent months, and at the same time select a node to retain transaction data for all time, the old data will only be automatically cleaned by the sliding window function, and There is no mechanism to modify existing data.

Further, it provides a pluggable automatic cleaning function, freely configures and stores transaction data in recent months, and selects a node to retain transaction data for all time, including the following steps:

(1) The node checks the blockchain according to the size of the sliding window set by the system, and finds that the number of complete blocks recently reserved by the blockchain is greater than the size of the sliding window, then execute (2);

(2) Keep all the blocks in the window and the genesis block, and delete the blocks outside the window and only keep the block header.

Combined with all the above technical solutions, the advantages and positive effects of the present invention are: in view of the problems of inefficiency in the above-mentioned data retrieval in the existing blockchain, and the lack of support for customized expansion, the present invention will be implemented in a distributed database system. Under the security reference structure, a highly flexible distributed double-layer data storage structure is designed, which solves the problem of single-point failure in traditional data systems and the performance bottleneck caused by the low query performance of traditional blockchain architecture. Based on the double-layer storage architecture, an efficient data self-inspection and inter-node mutual inspection method is proposed, which meets the enterprise's trusted storage requirements for sensitive data. A modular and configurable system architecture is proposed, which satisfies the scalability and compatibility of the system.

The present invention divides the data into two layers through layered design: the bottom layer is the data change increment stored in the block chain data structure, and the chain data structure has higher tail writing performance. The top layer is the final state set of data obtained by incremental changes in the underlying data, which is stored in a block structure and indexed using a B+ tree. The bottom layer uses the blockchain data structure for storage. Through regular self-checks of the chain structure's legitimacy, and through inter-node communication, the tampered data is corrected to ensure that the data on the chain cannot be tampered with. The final state of the top-level storage data, the node needs to self-check before operating the data in the top-level database to further improve the anti-tampering performance of the system. It provides a pluggable automatic cleaning function, supports a modular consensus mechanism replacement scheme, and supports the required functional expansion at the application layer under the existing blockchain double-layer architecture.

Description of drawings

In order to explain the technical solutions of the embodiments of the present application more clearly, the following will briefly introduce the drawings that need to be used in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

FIG. 1 is a flowchart of a method for constructing a blockchain-based high-performance tamper-proof database provided by an embodiment of the present invention.

FIG. 2 is a diagram of a two-layer architecture of an implementation provided by an embodiment of the present invention.

FIG. 3 is an architecture diagram of node mutual inspection and self-inspection implemented by an embodiment of the present invention.

FIG. 4 is an overall flow chart of the implementation provided by the embodiment of the present invention.

FIG. 5 is a sub-flow diagram of the structure of a two-layer database system based on a distributed peer-to-peer network implemented by an embodiment of the present invention.

FIG. 6 is a sub-flow chart of data self-checking and inter-node mutual checking with low time complexity implemented by an embodiment of the present invention.

FIG. 7 is a sub-flow diagram of the implemented modular and configurable system architecture provided by an embodiment of the present invention.

FIG. 8 is a time chart of the relationship between node self-checking and data volume in an experiment provided by an embodiment of the present invention.

FIG. 9 is a schematic diagram of the relationship between the number of nodes and the time of mutual inspection consensus nodes in an experiment provided by an embodiment of the present invention.

FIG. 10 is a schematic diagram of query throughput of different database systems in an experiment provided by an embodiment of the present invention.

FIG. 11 is a schematic diagram of a single-operation response time of different database systems in an experiment provided by an embodiment of the present invention.

detailed description

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

In view of the problems existing in the prior art, the present invention provides a method for constructing a high-performance anti-tampering database based on blockchain. The present invention is described in detail below with reference to the accompanying drawings.

As shown in Figure 1, the construction method of the high-performance tamper-proof database based on blockchain provided by the present invention includes the following steps:

S101: Double-layer database system structure based on distributed peer-to-peer network: The data is divided into two layers through hierarchical design: the bottom layer is the data change increment stored in the blockchain data structure, and the chain data structure has a higher tail Write performance, the top layer is the final state set of data obtained by incremental changes in the underlying data, which is stored in a block structure and uses a B+ tree to build an index;

S102: Data self-inspection and inter-node mutual inspection method with low time complexity: the bottom layer uses the blockchain data structure for storage, and the tampered data is corrected through regular self-inspection of the chain structure's legitimacy through inter-node communication. The final state of the top-level storage data, the node needs to self-check before operating the data in the top-level database to further improve the anti-tampering performance of the system;

S103: Modular and configurable system architecture: provides a pluggable automatic cleaning function, supports a modular and pluggable consensus mechanism, and supports the required functions at the application layer under the existing blockchain double-layer architecture Sexual Expansion.

The construction method of the blockchain-based high-performance tamper-resistant database provided by the present invention can also be implemented by those skilled in the industry by other steps. The construction method of the blockchain-based high-performance tamper-resistant database provided by the present invention in FIG. 1 Just one specific example.

The technical solutions of the present invention will be further described below with reference to the accompanying drawings.

The present invention designs a highly flexible distributed double-layer data storage structure under the security reference structure of the distributed database system, which solves the problem of single-point failure in the traditional data system and the problems caused by the low query performance of the traditional blockchain architecture. performance bottleneck. Based on the double-layer storage architecture, an efficient data self-check and inter-node mutual check method is proposed, which realizes the tamper-proof of the underlying data and satisfies the enterprise's trusted storage requirements for sensitive data. A modular and configurable system architecture is proposed, which satisfies the scalability and compatibility of the system.

The application principle of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 4 , the method for constructing a blockchain-based high-performance tamper-proof database according to an embodiment of the present invention includes the following steps:

S101: Two-tier database system structure based on distributed peer-to-peer network:

S102: Data self-checking and inter-node mutual checking method with low time complexity;

S103: Modular and configurable system architecture;

The above application principles included in the present invention will be described in detail below with reference to specific embodiments.

As shown in Figure 5, the steps of the present invention based on the double-layer database system structure of the distributed peer-to-peer network are as follows:

Step 1. Divide the data into 2 layers through hierarchical design;

1a) The bottom layer is the data change increment stored in the blockchain data structure, and the top layer is the final data state set obtained from the bottom layer data change increment. The bottom layer uses a relational database for structured storage, and the top layer can use the database type required by the business. In the present invention, the bottom and top databases are stored in the same database instance.

Step 2, the bottom layer is the incremental data change stored in the blockchain data structure, and the chain data structure has high tail write performance;

2a) Accept the user's on-chain request through the API, and broadcast the on-chain request among nodes in the form of a pending on-chain transaction. When the consensus block time arrives, the node will package the current on-chain transaction into a block and follow the block Chain data structure, stored in the underlying blockchain database;

Step 3, the top layer is the final state set of data obtained by the incremental change of the underlying data, which is stored in a block structure, and uses a B+ tree to establish an index at the same time;

3a) Whenever a node produces a block, or obtains an updated block from other nodes, it will incrementally reproduce the data changes in the new block to the top-level state database, which is the latest state. Use B+ tree to build index;

As shown in FIG. 6 , the steps of the low time complexity data self-checking and inter-node mutual checking method of the present invention are as follows;

Step 1, the bottom layer uses the blockchain data structure for storage, through regular self-checks on the validity of the chain structure, and corrects the tampered data through inter-node communication to ensure that the data on the chain cannot be tampered with.

1a) First, the node performs a self-check to check whether the hash before and after its own blockchain is correct; if it is not correct, it broadcasts a request message to the blockchain nodes with physical connections around it;

Request message: Node X broadcasts the message to obtain the lost block first to its one-hop node (neighbor node for short) that has a physical connection Request={Cert_X, t, Nonce, Sign(Sk _x , H(Cert_X||t||Nonce) )}. Among them, Cert_X represents the public key certificate of node X, t is the maximum block number of the current local blockchain, and Nonce is the selected random number.

Response message: After the neighbor node receives the Request, it first verifies its signature information to ensure the authenticity of the source of the request message and the integrity of the content, and then sends a response message Response containing the missing blockchain to the requesting node X. Taking one of the neighbor nodes K as an example, Response_K={Cert_K, Block_lost, Nonce+1, Sign(Sk _x , H(Cert_K||Block_lost||Nonce+1))}. Among them, Cert_K represents the public key certificate responding to the neighbor node K, and Block_lost represents the discarded block set Block_lost={Block _t+1 , …, Block _n } (assuming that the current latest block of the entire network is Block _n ). Node X will receive responses from multiple neighbor nodes, and recover all lost block data by selecting the response message that contains the most lost block sets and is valid for verification. The verification here includes the verification of the chain relationship in the block and the verification of the signed message;

Step 2, the top-level database needs to self-check before operating the data;

2a) The node calculates the hash value of the current latest state of the top-level database, broadcasts the hash value to the entire network, and then confirms that the state of its top-level database is consistent across the entire network with the help of the modular consensus protocol.

2b) If the node learns that the current hash value of its top-level database is different from that of the entire network by more than 1/2 through the consensus process, the node will call the self-inspection and mutual-inspection process of the underlying blockchain to update the latest data of the underlying and top-level databases. state synchronization;

2c) If the node confirms that the current hash value of its top-level database is consistent with more than 1/2 of the nodes in the entire network through the consensus process, it will continue to add, delete, and modify the database. This is done by sending the SQL statement of the top-level database operation to The underlying blockchain database network is implemented.

As shown in Figure 7, the steps of the modular and configurable system architecture of the present invention are as follows:

Step 1, support a modular consensus mechanism replacement scheme for the underlying blockchain database;

1a) Built-in Raft-based consensus protocol with both security and consensus efficiency. Users can also switch to the PBFT consensus protocol with higher security, or manually specify the block time to ensure the efficiency of the system.

Step 2, the top-level database supports data access through various interfaces, and is compatible with various common database accesses;

2a) Including relational database databases such as postgres, mysql, etc., which supports users to choose according to business needs. Support queryers to submit query requests using standard SQL statements, including complex operations such as filtering, clustering, joining, and sorting. Enterprises can directly switch the back-end relational database of the existing business system to this database system without too much adaptation;

Step 3. Support under the existing blockchain double-layer architecture. Functional extensions that may be required are made at the application layer.

3a) The built-in system provides a pluggable automatic cleaning function, which can be freely configured to store transaction data in recent months, and at the same time select a node to retain transaction data for all time. Old data will only be automatically cleaned up by the sliding window function, and there is no mechanism to modify existing data;

Comparison with existing technology:

(1) Compared with the traditional database, the anti-tampering database based on the block chain designed by the present invention has significant advantages in terms of security. Specifically, the traditional database adopts a centralized architecture, and the addition, deletion and modification of data are completed by a single node, which cannot prevent and detect malicious deletion and modification of data after a single node is compromised by attackers, nor can it prevent nodes from writing to the database. Enter fake data. The tamper-proof database based on the blockchain designed by the present invention combines the blockchain with the local database, which can effectively solve the security bottleneck of the traditional database. Since the data is distributed and stored in a plurality of nodes in the network, the present invention can effectively detect and prevent malicious addition, tampering and deletion of data by malicious nodes. In addition, data in traditional databases are often stored in a single node, which makes the data face a more serious single-point failure problem. The present invention can effectively solve this problem of the traditional database by using the block chain technology. The comparison of the anti-tampering database based on the block chain designed by the present invention and the traditional database is shown in Table 1. Compared with the traditional database, the blockchain-based database designed by the present invention has obvious advantages in anti-tampering, anti-deletion, and anti-single point failure.

Table 1 The project of the present invention is compared with the traditional database

(2) Comparison with other blockchain databases

Table 2. Comparison between the database of the present invention and the existing blockchain database

At present, there are relatively few database research and products based on blockchain, among which the most representative achievements are the decentralized open source public blockchain platform Ethereum, and the blockchain-based database application platform ChainSQL. In Ethereum, various applications including data storage can be implemented through the smart contracts provided by the platform, and it is difficult to implement functions such as pluggability, and the data query efficiency is low. In ChainSQL, each instruction of a database operation is recorded in a transaction, that is, a transaction corresponds to a database operation, and the blockchain network records all operations on the database in the form of transactions. For a blockchain node configured with a database, operations on the database are completed while the blockchain network records transactions. For network nodes without database configuration, transactions will only be recorded in the block of this node. Although ChainSQL also implements blockchain-based data tamper-proof storage and can realize the combination of blockchain and traditional databases, ChainSQL mainly has the following shortcomings: (1) It cannot reduce the storage burden of nodes; (2) Periodic self-inspection and mutual inspection of on-chain data are not considered. The performance comparison between the tamper-proof blockchain database designed by the present invention and ChainSQL is shown in Table 2. Compared with the ChainSQL database, the anti-tampering database designed by the present invention has obvious advantages in the convenience of customizable and lightweight storage of data.

After functional comparison, the designed blockchain tamper-proof database is compared with the existing blockchain database service in throughput and response time of a single operation, as shown in Figure 10 and Figure 11.

The test results show that, compared with the existing blockchain database, the designed high-performance anti-tampering database system based on blockchain improves the concurrent query performance by about 70%, and performs addition and deletion in the database of millions of records. , change, check and other operations response time does not exceed 100ms.

In terms of the performance of the impact of data volume on node self-checking, the present invention deploys a virtual machine for testing (8 cores and 8G), and the test result is shown in FIG. 10 . As the amount of data increases, so does the time it takes for the node to self-check.

Regarding the influence of the number of consensus nodes on the mutual inspection performance of nodes, the present invention deploys a virtual machine for testing (8 cores and 8G), and the test results are shown in FIG. 9 . As the number of consensus increases, the time spent on node self-checking also increases gradually.

The invention designs a highly flexible distributed double-layer data storage structure under the security reference structure of the distributed database system, and solves the problem of single point failure in traditional data systems and the performance caused by the low query performance of traditional blockchain architecture. bottleneck. Based on the double-layer storage architecture, an efficient data self-check and inter-node mutual check method is proposed, which realizes data tamper-proof. A modular and configurable system architecture is proposed, which satisfies the scalability and compatibility of the system. The methods include: a two-layer database system structure based on a distributed peer-to-peer network: the data is divided into two layers through a layered design: the bottom layer is the data change increment stored in the blockchain data structure, and the chain data structure has higher tail write performance. The top layer is the final state set of data obtained by incremental changes of the underlying data, which is stored in a block structure and indexed using a B+ tree. Data self-checking and inter-node mutual checking method with low time complexity: The bottom layer uses the blockchain data structure for storage, and the tampered data is corrected through regular self-checking of the chain structure's legitimacy through inter-node communication. The final state of the top-level storage data, the node needs to self-check before operating the data in the top-level database to further improve the anti-tampering performance of the system. Modular and configurable system architecture: provides a pluggable automatic cleaning function, supports a modular and pluggable consensus mechanism, and supports the required functional expansion at the application layer under the existing blockchain double-layer architecture .

This method designs a two-layer database system structure of a distributed peer-to-peer network, a data verification method for data self-checking and mutual checking between nodes, and applies it to the blockchain system as a distributed and tamper-resistant database system. It is used to store the final state data and block data, realizes data tamper-proof and anti-deletion in the double-layer database architecture, realizes the customization and expansion of system functions, and meets the needs of enterprises for trusted storage of sensitive data. .

It should be noted that the embodiments of the present invention may be implemented by hardware, software, or a combination of software and hardware. The hardware portion may be implemented using special purpose logic; the software portion may be stored in memory and executed by a suitable instruction execution system, such as a microprocessor or specially designed hardware. Those of ordinary skill in the art will appreciate that the apparatus and methods described above may be implemented using computer-executable instructions and/or embodied in processor control code, for example on a carrier medium such as a disk, CD or DVD-ROM, such as a read-only memory Such code is provided on a programmable memory (firmware) or a data carrier such as an optical or electronic signal carrier. The device and its modules of the present invention can be implemented by hardware circuits such as very large scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., It can also be implemented by software executed by various types of processors, or by a combination of the above-mentioned hardware circuits and software, such as firmware.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. Any person skilled in the art is within the technical scope disclosed by the present invention, and all within the spirit and principle of the present invention Any modifications, equivalent replacements and improvements made within the scope of the present invention should be included within the protection scope of the present invention.

Claims

A method for constructing a high-performance anti-tampering database based on blockchain, characterized in that, the method for constructing the high-performance anti-tampering database based on blockchain comprises:

Two-layer database system structure based on distributed peer-to-peer network: data is divided into two layers through hierarchical design, the bottom layer is the incremental data change stored in the blockchain data structure, and the chain data structure has a higher tail write Performance, the top layer is the final state set of data obtained by incremental changes in the underlying data, which is stored in a block structure, and uses a B+ tree to build an index;

Data self-inspection and inter-node mutual inspection method with low time complexity: the bottom layer uses the blockchain data structure for storage, through regular self-inspection of the chain structure's legitimacy, and through inter-node communication to correct the tampered data, the top layer is stored The final state of the data, the top-level database performs self-checks before operating on the data;

Modular and configurable system architecture: It provides a pluggable automatic cleaning function, supports a modular consensus mechanism replacement scheme, and supports the required functional expansion at the application layer under the existing blockchain double-layer architecture.
The method for constructing a high-performance anti-tampering database based on blockchain according to claim 1, wherein the method for constructing the high-performance anti-tampering database based on blockchain comprises:

(1) Double-layer database system structure based on distributed peer-to-peer network;

(2) Data self-checking and inter-node mutual checking methods with low time complexity;

(3) Modular and configurable system architecture.
The method for constructing a blockchain-based high-performance tamper-resistant database according to claim 2, wherein the distributed peer-to-peer network-based double-layer database system structure comprises the following steps:

Step 1: Divide the data into two layers through hierarchical design;

Step 2, the bottom layer is the incremental data change stored in the blockchain data structure, and the chain data structure has higher tail write performance;

Step 3: The top layer is the final state set of data obtained by incremental changes of the underlying data, which is stored in a block structure and indexed using a B+ tree.
The method for constructing a blockchain-based high-performance tamper-resistant database according to claim 3, wherein the step 1 divides the data into two layers by hierarchical design and includes the following steps: the bottom layer is to use blockchain data Incremental data change in structured storage, the top layer is the final state set of data obtained by incremental data change at the bottom layer; the bottom layer uses a relational database for structured storage, and the top layer uses the database type required by the business.
The method for constructing a blockchain-based high-performance tamper-proof database according to claim 3, wherein in the second step, the bottom layer is a data change increment stored in a blockchain data structure, and the chain data structure has High tail write performance, including the following steps:

(1) Accept the user's on-chain request through the API;

(2) The on-chain request is broadcast among nodes in the form of a pending on-chain transaction;

(3) When the consensus block time arrives, the node will package the current transaction to be listed as a block;

(4) Follow the blockchain data structure and store in the underlying blockchain database.
The method for constructing a high-performance anti-tampering database based on blockchain according to claim 3, wherein in the step 3, the top layer is the final state set of data obtained by incremental changes of the bottom layer data, which is stored in a block structure. , while using B+ tree to build index, which has high query performance, including the following steps:

(1) Whenever a node generates a block or obtains an updated block from other nodes, the incremental data changes in the new block will be reproduced to the top-level state database, and the top-level state database will be the latest state;

(2) Use the B+ tree to build an index.
The method for constructing a blockchain-based high-performance tamper-proof database according to claim 2, wherein the low-time-complexity data self-checking and inter-node mutual checking method comprises the following steps:

(1) The bottom layer adopts the blockchain data structure for storage, and the tampered data is corrected through the regular self-check of the chain structure's legitimacy and communication between nodes;

(2) The top-level database performs self-inspection before operating the data.
The method for constructing a blockchain-based high-performance tamper-proof database according to claim 7, wherein in the step 1, the bottom layer adopts a blockchain data structure for storage, and the validity of the chain structure is automatically checked by periodically checking the validity of the chain structure. Check and correct the tampered data through inter-node communication to ensure that the data on the chain cannot be tampered with; including the following steps:

(1) First, the node performs a self-check to check whether the hash before and after its own blockchain is correct; if it is not performed correctly (2); the node performs a self-check on the top-level database before operating the data; including the following steps:

The node calculates the hash value of the latest state of the top-level database, broadcasts the hash value to the entire network, and then uses the modular consensus protocol to confirm that the state of its top-level database is currently consistent across the entire network;

If the node learns that the current hash value of its top-level database is different from that of the entire network by more than 1/2 through the consensus process, the node will call the self-inspection and mutual-inspection process of the underlying blockchain to check the latest status of the bottom and top-level databases. Synchronize;

If the node confirms that the current hash value of its top-level database is consistent with more than 1/2 of the nodes in the entire network through the consensus process, it will continue to add, delete, and modify the database, and send the SQL statement of the top-level database operation to the underlying blockchain. Database network to achieve;

(2) Broadcast a request message to the blockchain nodes with physical connections around it; including the following steps:

1) Request message: Node X first broadcasts the message Request={Cert_X, t, Nonce, Sign(Sk x , H(Cert_X||t||Nonce))}; Among them, Cert_X represents the public key certificate of node X, t is the maximum block number of the current local blockchain, and Nonce is the selected random number;

2) Response message: After the neighbor node receives the Request, it first verifies its signature information to ensure the authenticity of the source of the request message and the integrity of the content, and then sends a response message Response containing the missing blockchain to the requesting node X ; Take one of the neighbor nodes K as an example, Response_K={Cert_K, Block_lost, Nonce+1, Sign(Sk x , H(Cert_K||Block_lost||Nonce+1))}; wherein, Cert_K represents the response of the neighbor node K Public key certificate, Block_lost indicates the discarded block set Block_lost={Block t+1 ,..., Block n } (assuming that the latest block of the entire network is Block n ), node X will receive responses from multiple neighbor nodes , restore all lost block data by selecting the response message that contains the most lost block sets and is valid for verification. The verification includes the verification of the chain relationship in the block and the verification of the signed message.
The method for constructing a blockchain-based high-performance tamper-proof database according to claim 2, wherein the modular and configurable system architecture comprises the following steps:

(1) For the underlying blockchain database, a modular consensus mechanism replacement scheme is supported, and a Raft-based consensus protocol with both security and consensus efficiency is built in. Users can also switch to the PBFT consensus protocol with higher security, or Manually specify the block time;

(2) The top-level database supports data access through various interfaces, compatible with various common database accesses, including relational databases postgres, mysql, supports users to choose according to business needs, and supports queryers to submit query requests using standard SQL statements, including Filter, cluster, join, sort complex operations;

(3) Provides a pluggable automatic cleaning function, which can be freely configured to store transaction data in recent months, and at the same time select a node to retain transaction data for all time, the old data will only be automatically cleaned by the sliding window function, and There is no mechanism to modify existing data;

Provides a pluggable automatic cleaning function, freely configures and stores transaction data in recent months, and selects a node to retain transaction data for all time, including the following steps:

1) The node checks the blockchain according to the size of the sliding window set by the system, and finds that the number of complete blocks recently reserved by the blockchain is greater than the size of the sliding window, then execute 2);

2) Keep all the blocks in the window and the genesis block, and delete the blocks outside the window and only keep the block header.
A database constructed by the method for constructing a blockchain-based high-performance tamper-proof database according to any one of claims 1 to 9.